【leetcode❤python】232. Implement Queue using Stacks

#-*- coding: UTF-8 -*-
#双栈法
class Queue(object):
    def __init__(self):
        """
        initialize your data structure here.
        """
        self.inStack=[]
        self.outStack=[]
        

    def push(self, x):
        """
        :type x: int
        :rtype: nothing
        """
        self.inStack.append(x)
        

    def pop(self):
        """
        :rtype: nothing
        """
        self.peek()
        self.outStack.pop()
        

    def peek(self):
        """
        :rtype: int
        """
        if not self.outStack:
            while self.inStack:
                self.outStack.append(self.inStack.pop())
        return self.outStack[-1]
        

    def empty(self):
        """
        :rtype: bool
        """
        return True if (len(self.inStack)+len(self.outStack))==0 else False

原文地址:https://www.cnblogs.com/kwangeline/p/5953582.html